This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 21 |
| 5 | 87 |
| 6 | 612 |
| 7 | 3649 |
| 8 | 35515 |
| 9 | 289927 |
| 10 | 377118 |
| 11 | 36947363 |
| 12 | 657510251 |
| 13 | 7736272845 |